Process to prepare a lubricating base oil and a gas oil

Abstract

Process to prepare two or more lubricating base oil grades and a gas oil by (a) hydrocracking/hydroisomerisating a Fischer-Tropsch product, wherein weight ratio of compounds having at least 60 or more carbon atoms and compounds having at least 30 carbon atoms in the Fischer-Tropsch product is at least 0.2 and wherein at least 30 wt % of compounds in the Fischer-Tropsch product have at least 30 carbon atoms, (b) separating the product of step (a) into one or more gas oil fractions and a base oil precursor fraction, (c) performing a pour point reducing step to the base oil precursor fraction obtained in step (b), and (d) separating the effluent of step (c) in two or more base oil grades.

1 . Process to prepare two or more lubricating base oil grades and a gas oil by 
 (a) hydrocracking/hydroisomerisating a Fischer-Tropsch product, wherein weight ratio of compounds having at least 60 or more carbon atoms and compounds having at least 30 carbon atoms in the Fischer-Tropsch product is at least 0.2 and wherein at least 30 wt % of compounds in the Fischer-Tropsch product have at least 30 carbon atoms,    (b) separating the product of step (a) into one or more gas oil fractions and a base oil precursor fraction,    (c) performing a pour point reducing step to the base oil precursor fraction obtained in step (b), and    (d) separating the effluent of step (c) in two or more base oil grades.    
     
     
         2 . Process according to  claim 1 , wherein at least 50 wt % of compounds in the Fischer-Tropsch product have at least 30 carbon atoms.  
     
     
         3 . Process according to any one of claims  1 - 2 , wherein the weight ratio of compounds having at least 60 or more carbon atoms and compounds having at least 30 carbon atoms in the Fischer-Tropsch product is at least 0.4.  
     
     
         4 . Process according to any one of claims  1 - 3 , wherein the conversion in step (a) is between 25 and 70 wt %.  
     
     
         5 . Process according to any one of claims  1 - 4 , wherein the base oil precursor fraction has an initial boiling point of between 330 and 400° C.  
     
     
         6 . Process according to any one of claims  1 - 5 , wherein step (c) is performed by means of solvent dewaxing.  
     
     
         7 . Process according to any one of claims  1 - 5 , wherein step (c) is performed by means of catalytic dewaxing.  
     
     
         8 . Process according to  claim 7 , wherein the catalytic dewaxing catalyst comprises a zeolite having a pore diameter of between 0.35 and 0.8 nm, a Group VIII metal and a binder.  
     
     
         9 . Process according to  claim 8 , wherein the binder is a low acidity refractory oxide binder which is essentially free of alumina and wherein the catalyst is obtained by contacting an extrudate of zeolite and binder with an aqueous solution of fluorosilicate salt.  
     
     
         10 . Process according to  claim 9 , wherein step (c) is performed at a temperature between 275 and 375° C. and a pressure of between 40 and 70 bars to obtain base oils having a pour point of below −60 and up to −10° C.  
     
     
         11 . Base oil having a kinematic viscosity at 100° C. of between 12 and 30 cSt, a viscosity index of greater than 125 and an evaporation loss after 1 hour at 250° C. of at most 0.5 wt %.  
     
     
         12 . Use of base oil according to  claim 11  as a plasticizer.  
     
     
         13 . Use of the base oil according to  claim 11  as a mould release process oil.